THE 'KAREZ' The Karez System,... by SirRichard
THE 'KAREZ'The Karez System, an irrigation system of wells connected by underground channels, is considered as one of the three great ancient projects in China, the other two being the Great Wall and the Grand Canal. There are in the Turpan area nearly one thousand karez totaling 5000 kilometers in length.
The structure of the karez basically consists of wells, underground channels, ground canals and small reservoirs. In spring and summer, a great mount of melting snow and rainfall flow down from the Bogda and Karawuqunta mountains north and west of the Turpan Depression into the valleys and then seep into the Gobi Desert. Taking advantage of the mountain slopes, the working people ingeniously created the karez to draw the underground water to irrigate the farmland. The water in karez will not evaporate in large quantities even under the scorching heat and fierce wind, hence ensuring a stable water flow and gravity irrigation.